Apparatus for making a slide-fastener coupling coil

ABSTRACT

An apparatus for making a slide-fastener coupling coil comprises a mandrel mounted on a support having a pair of portions with noncoincident, advantageously parallel, axes. Mechanism is provided rotatable about each of the mechanisms for winding a synthetic-resin monofilament around the mandrel. A supply of filler cord can be provided between the mechanisms, and this cord can be fed to the mandrel through a longitudinal passage in the support. The downstream mechanism can be arranged to hold the tension in the monofilament at the same level.

O United States Patent 1151 3,680,604 Frohlich et a1. Aug. 1, 1972 [54]APPARATUS FOR MAKING A SLIDE- 3,l21,256 2/1964 Fleisher ..18/19 FASTENERCOUPLING COIL 3,137,037 6/1964 Wilcken ..18/19 [72] Inventors: AlfonsFrohfich; Franz h n; 3,353,217 11/1967 Bashover ..18/19 WernerRademacher, all of Essen, Gel-many Primary Examiner-Lowell A. Larson[73] Assignee: Opti-Holding AG, Glarus, Switzer- Attorney-Karl Ross 57ABSTRACT 7 [22) Flled Sept 14 19 0 An apparatus for makmg asllde-fastener couphng 0011 PP 71,923 comprises a mandrel mounted on asupport having a pair of portions with noncoincident, advantageously[30} Foreign Application Priority Data parallel, axes. Mechanism isprovided rotatable about each of the mechanisms for winding asynthetic-resin Sept. 16, 1969 Germany ..P 19 46 702.8 monofilamemaround the mandreL A p y of finer ..140 92.1 18 19 C, 57 138 cord can beprovided between the mechanisms and .....B2lf 2/04 this cord can be fedto the mandrel through a longitu- [58] Field 61 Search ..140/92.1;57/138; 18/19 c; dmal Passage in the pp The downstream 29/410 mechanismcan be arranged to hold the tension in the monofilament at the samelevel. [56] Refe'ences c'ted 11 Claims, 6 Drawing Figures UNITED STATESPATENTS 3,071,917 1/1963 Fisher ..18/19 PATENTEDAua 1 m2 v 3,5 0, 0

sum 1 or s Q I Lg Q, A. Frb'h/ich N E Hochlehnerf W. RademacherINVEN'IURS'.

m/ ,1 I Wag.

Attorn y PAIENTEm c' H912 SHEEI 3 or 5 A. FR'OHLICH F. HOCHLEHNERT W.RADEMACHER INVENTORS.

BY ss a RD ATTORNEY PATENTEDMI: i m

SHEET 5 BF 5 T R E HN H m H "0c O FH A F 6 G F W. RADEMACHER INVENTORSBY {Karl (Ross ATTORNEY FIELD OF THE INVENTION The present inventionrelates to an apparatus for making a slide-fastener coupling element,particularly a coil from a synthetic-resin monofilament.

BACKGROUND OF THE INVENTION In order to make such a coil themonofilament must be wound around a mandrel. To this end it must be fedto the mandrel with as little twist as possible and removed therefromwith as little deformation as possible. In addition, since the turns ofthe coil must be somewhat elongated, the mandrel must have a crosssection resembling a flattened circle. Thus, it is also mandatory thatthis mandrel not rotate about its own axis.

To prevent this rotation two principal methods have been used: Themandrel is simply fixed to a support at its upstream end, and the supplyof monofilament is orbited around it. In this case the winding speedmust be held low since the centripetal force developed by a large spoolof, for example, nylon filament, is considerable. In the other knownmethod the filament is fed axially toward the elongated mandrel, whichmust then be prevented from rotating by some indirect means. The mandrelcan be provided with an off-center weight to prevent its rotation, or itcan be gripped magnetically. In both of these cases oscillations canbuild up in the mandrel, making for poor tolerances in the finishedcoil. Another method of restraining the mandrel provides a planetarygear arrangement whereby the mandrel is fixed to a sun gear whose planetgear are driven in such a manner that the sun gear does not rotate. Thissystem has the disadvantage that it is extremely expensive in therealization, and that it is impossible to vary the tension of themonofilament about the mandrel by speeding up or slowing down thewinding speed, since this will cause the mandrel to rotate.

OBJECTS OF THE INVENTION It is, therefore, an object of the presentinvention to provide an improved apparatus for making a slidefastenercoupling coil.

Another object is to provide such an apparatus which overcomes theabove-mentioned disadvantages.

SUMMARY OF THE INVENTION The above objects are attained according to thepresent invention with an apparatus wherein the monofilament is fedaxially toward the mandrel which isitself mounted on a support having apair of portions with noncoincident axes. The monofilament is fed towardand wound on the mandrel by a pair of mechanism each rotatable about oneof the axes of the support. The feature that the support comprises thesetwo nonaligned portions makes it impossible for it to rotate, eventhrough it is solely supported by bearings in two separate mechanismsrotating in the same sense at the same rate. According to anotherfeature of the present invention, the two axes are parallel but offsetfrom each other, so that the support is in efi'ect a crank. In this casethe term mandrel is meant only to refer to the element around which thecoil is wound, since the mandrel rod itself could be unitary with thesupport, could constitute one of the portions thereof, or could simplybe mounted thereon.

Drive means is provided for synchronously rotating the two mechanisms atthe same rate. According to yet another feature the downstreammechanism, i.e., that mechanism nearer the mandrel, is provided withmeans for maintaining constant the length of the path for themonofilament from the upstream mechanism to the mandrel. Since the twoaxes are offset, as the mechanisms rotate this path will change inlength to bring about a possible disadvantageous stressing of thefilament. To this end the means includes a body mounted in thedownstream mechanism and having a central axis rotatable about thedownstream axis. This member is provided with an eccentric guide passagefor the filament, and it is arranged so that the eccentric passage doesnot rotate about the bodys central axis, the eccentricity beingdimensioned such that the variation in path length on rotation is fullycompensated for. In another arrangement the mandrel is mounted offsetfrom the downstream portion to an extent sufficient to compensate forthe path variations.

DESCRIPTION OF THE DRAWING The above and other objects, features, andadvantages will become apparent from the following description,reference being made to the accompanying drawing, in which: I

FIG. 1 is a side view of the apparatus according to the presentinvention;

FIG. 2 is a top view of the installation shown in FIG.

FIG. 3 is a detail of FIG. 2;

FIG. 4 is a detail of FIG. 1 in section;

FIG. 5 is an end view of the detail of FIG. 4; and

FIG. 6 is a view similar to FIG. 3 showing an alternative embodiment ofthe present invention.

SPECIFIC DESCRIPTION As shown in FIGS. 1 4, the installation for makinga coupling element has a supply I of a synthetic-resin monofilament 2,here Nylon, on tow spools 4 which can be rotatable about their axes 4a,but which need not be. Three more spools and filaments can be provided,if desired. Unwinding devices 40 are provided and guide rollers 41 forleading the filaments 2 up to a feed arrangement 3 which comprises fourrollers 20. Each filament is wound several times around two of therollers 20 so that it is pulled 011 its spool 4 at a rate determined bythe transmission 42 connected to a motor 21 serving as drive. Thistransmission 42 is of the variable-speed type and is connected throughbelts 43 to the rollers 20 so that it can be adjusted to determine thewinding tension as will seen below. The whole apparatus is mounted on acommon frame 13.

Downstream, that is, in the transport direction T, is a muffle 44 inwhich the thermoplastic filaments 2 are somewhat softened whence theyeach pass between a pair of toothed driven wheels or rollers 17 and 18which positively engage the filaments 2 and form coupling heads 9thereon. Subsequently the stamped filaments 2 are fed through a firstfeeding-winding mechanism 7 and then a second feeding-winding mechanism8 where they are wound around a mandrel 6 at a rate determined by thefeed speed determined by the transmission 42 and rotation rate of thetwo mechanisms 7 and 8 which are connected via timing belts 30 to themotor 21.

A coil 11 is thus formed which is engaged by a toothed wheel 10downstream of the mandrel 6 and passed onto a heated drum 12 providedwith serrated grooves in which the individual coil turns are receivedand thermally fixed. Thence the finished coils 11 are dropped into acontainer 45.

FIGS. 3 show the mechanisms 7 and8 in greater detail. The mechanism 7 isrotatable about an axis B which is the longitudinal axis of a portion 5aof a mandrel support 5.11m other portion 5b of the mandrel support 5 hasa longitudinal axis A offset from and parallel to the axis B and servingas the rotation axis for the downstream mechanism 8. The two portions 5aand 5b are joined together by a central crank portion 14.

Due to the offset axes A and B of the two portions, the rotation of thetwo mechanisms 7 and 8 cannot cause the support 5 to rotate, both oftheseaxes being fixed.

The mandrel 6 has a rounded elongated cross section, as shown in FIG. 5,with its long sides vertical. It is mounted on the portion 5b and iscoaxial therewith. The spacing of the coupling heads 9 is such that theyalways find themselves on the short rounded up and down sides of themandrel 6 as the filaments 2 are wound therearound.

The mechanism 7 comprises an element 46 journaled in abracket 47 securedto the machine frame 13. The mechanism 8 is basically a blocklikecylindrical element 35 journaled in a support 34 also mounted on theframe 13. Both elements 35 and 46 are connected to the motor'2l bytiming belts 30 so that they rotate in the same sense at exactly thesame rates.

Upstream of the mechanism 7 is an arrangement 27 for holding av spool28carrying a supply of filler cord 25. This cord 25 is fed ofi' through aunwinding mechanes 29 whence it passes through a passage 26 formedthrough the entire length of the support 5, so that the ,cord 25 exitsat the mandrel 6 where the filament 2 is wound around it. The spool 28is gripped between two rubber cones 31 and 32. The cone 32 is mounted onthe upstream end of the support 5, as is the unwinding arm 29. The cone31 is mounted on a shaft 54 journaled in an element 49 in turn journaledin a bracket 52 on the machine frame 13. A spring 55 urges the cone 31toward the cone 32 to grip the spool 28. The element 49 is connected tothe motor 21 via a timing belt 30 so that it also turns at the same rateand in the same sense as the mechanisms 7 and 8. The tension of thefilter cord 25 is determined by friction of the spool 28 on the cone 32.Elements 49 and 46 are formed with respective flanges 56 and 48 providedwith 'in-line holes 50 through which the filament 2 is guided.

In addition the filament 2 passes the bracket 52 by passing througha'bore 51 in the element'49 and passes the bracket 47 by passing througha bore 53 in the element 46. In this manner, the length of the path forthe filament 2 from spool 4 to a point 15 where the filament 2 entersthe bore 53 is always essentially the same, even when the motor 21 isrotating the mechanisms 7 and 8 and the element 49.

With particular reference to FIGS. 4 and 5 it can be seen that thecylindrical element 35, which is rotatable about the axis A, rotatablymounts a rod '22 having a central axis C parallel to and offset from thetires A and B. This rod 22 further has a throughgoing axial bore '23which has an axis D ofi'set from" the axis 'C. Both the portion 5b andthe rod 22 are provided with identical gears 24 interconnected by asmall pinion 240 so that," as the element 35 rotates about the axis 'A,the axis C of the rod 22 describes a circular orbit C' concentric withthe axis A and the oficenter axis D describes a circular orbit D' to theleft in FIG. 5 of the orbit C. Ofzcourse, due to the immobility of thegear 24 on the portion 5b and the fact that'the gear 24 on the rod 22has the same diameter and number of teeth, the rod does not rotate aboutits own axis. In this manner, with the apparatus dimensioned such thatfour times the radial distance between the axes C and D equals theradial distance between the axes A and B, the length of the path for thefilament 2 between the point 15 and a point 16 where t the filament 2engages the mandrel 6 remains essentially constant as the mechanisms 7and 8 rotate. In

other words, as the rod 22 rotates'into the position where it isfarthest from the axis B, the bore 23 is directly between the axis C andthe axis B, while when the rod 22 is closest to the axis B, the bore 23is on the other side of the axis C from the axis B. This effect isdoubled by the fact that the length of paths 37. and38' between theupstream and downstream ends, respecspecial effects, i.e., flattening,on the mandrel with the filament. It is also possible to provide atransmission with, for example, epicyclic gearing, so that the filamentfeed speed is varied tocompensate for the path length variations.

FIG. 6 shows another embodiment wherein the filament 2 simply passesthrough an axial bore 23' inthe element 35. But here a cranklike mandrel6 is provided which has a portion 60 having an axis E parallel to andofiset from the axis A by a distance equal to the distance between axesA and B, but loffset therefrom. In this arrangement, as path 37lengthens, path 38' shortens, and vice versa. Thus, the overall pathlength remains constant.

We claim: 1. An apparatus for making a slide-fastener coupling coilcomprising:

a mandrel; a support for said mandrel having a air of portions withnoncoincident axes; and means for feeding a filament toward said mandreland winding said filament around said mandrel, said means includingrespective mechanisms carrying said filament and rotatable about saidaxes. 2. The apparatus defined in claim 1, further comprismg:

drive means for synchronously rotating said mechanisms about said axesin the same sense and at the same rate; and

supply means nonrotatable about either of said axes for feeding afilament to said mechanisms.

3. The apparatus defined in claim 2 wherein said axes are parallel toand offset from each other.

4. The apparatus defined in claim 3 wherein said mandrel is coaxial withone of said axes.

5. The apparatus defined in claim 2 wherein said supply means includesmeans upstream of said mechanisms positively engaging said filament.

6. The apparatus defined in claim 2 wherein said mechanisms include adownstream mechanism and an upstream mechanism, said downstreammechanism having a downstream-mechanism axis and comprising:

an element rotatable about the downstreammechanism axis, said mandrelbeing coaxial therewith;

a body mounted in said element for rotation about a central axisparallel to said downstreammechanism axis, said body being formed with aguide passage offset from said central axis; and

means inhibiting rotation of said body about said central axis wherebyon rotation of said element said guide passage defines an orbiteccentric to said downstream-mechanism axis.

7. The apparatus defined in claim 6 wherein said means inhibitingrotation includes a pair of like gears,

one of said gears being mounted on the downstream portion of saidsupport and the other of said gears being mounted on said body.

8. The apparatus defined in claim 6 wherein said guide passage, saidcentral axis, and said downstreammechanism axis are all parallel andmutually offset, said guide passage being offset from said central axisby a distance equal to one-fourth of the distance said central axis isoffset from said downstream-mechanism axis.

9. The apparatus defined in claim 2 wherein said mandrel has an axisparallel to and offset from said axes of said portions.

10. The apparatus defined in claim 2, further comprising a supply offiller cord, guide means for carrying said cord from said supply to saidmandrel including a passage formed through said support and a supplyholder on said support.

11. The apparatus defined in claim 2 wherein said supply means includesmeans upstream of said mechanisms positively engaging said filament forfeeding same at a predetermined rate toward said mandrel, saidmechanisms rotating at a rate determined by said drive means, saidapparatus further comprising means operatively connected to said drivemeans for varying one of said rates relative to the other of said rates.

1. An apparatus for making a slide-fastener coupling coil comprising: amandrel; a support for said mandrel having a air of portions withnoncoincident axes; and means for feeding a filament toward said mandreland winding said filament around said mandrel, said means includingrespective mechanisms carrying said filament and rotatable about saidaxes.
 2. The apparatus defined in claim 1, further comprising: drivemeans for synchronously rotating said mechanisms about said axes in thesame sense and at the same rate; and supply means nonrotatable abouteither of said axes for feeding a filament to said mechanisms.
 3. Theapparatus defined in claim 2 wherein said axes are parallel to andoffset from each other.
 4. The apparatus defined in claim 3 wherein saidmandrel is coaxial with one of said axes.
 5. The apparatus defined inclaim 2 wherein said supply means includes means upstream of saidmechanisms positively engaging said filament.
 6. The apparatus definedin claim 2 wherein said mechanisms include a downstream mechanism and anupstream mechanism, said downstream mechanism having adownstream-mechanism axis and comprising: an element rotatable about thedownstream-mechanism axis, said mandrel being coaxial therewith; a bodymounted in said element for rotation about a central axis parallel tosaid downstream-mechanism axis, said body being formed with a guidepassage offset from said central axis; and means inhibiting rotation ofsaid body about said central axis whereby on rotation of said elementsaid guide passage defines an orbit eccentric to saiddownstream-mechanism axis.
 7. The apparatus defined in claim 6 whereinsaid means inhibiting rotation includes a pair of like gears, one ofsaid gears being mounted on the downstream portion of said support andthe other of said gears being mounted on said body.
 8. The apparatusdefined in claim 6 wherein said guide passage, said central axis, andsaid downstream-mechanism axis are all parallel and mutually offset,said guide passage being offset from said central axis by a distanceequal to one-fourth of the distance said central axis is offset fromsaid downstream-mechanism axis.
 9. The apparatus defined in claim 2wherein said mandrel has an axis parallel to and offset from said axesof said portions.
 10. The apparatus defined in claim 2, furthercomprising a supply of filler cord, guide means for carrying said cordfrom said supply to said mandrel including a passage formed through saidsupport and a supply holder on said support.
 11. The apparatus definedin claim 2 wherein said supply means includes means upstream of saidmechanisms positively engaging said filament for feeding same at apredetermined rate toward said mandrel, said mechanisms rotating at arate determined by said drive means, said apparatus further comprisingmeans operatively connected to said drive means for varying one of saidrates relative to the other of said rates.